But the Backup-Link in the 2 modules are a 169-IP-address wich is a little suspicous for me. Also I tried to reboot one of the 2 IOM. I first set the 2 external ports to down wich sets also the internal ports down. That makes me a bit wondering. But the connection was still okay and the other IOM did all the work.

Than I reloaded the first IOM wich was offline and after it was back the connection to the servers was lost for appr. a minute. And this is totaly weird in my opinion.

The Dashboard of the 2 IOMs say it is all okay and VLT is up and running with all necessary links and heartbeats and so on. But why is after a reload the connection lost for a while?

"The delay-restore feature waits for all saved Configurations to be applied, then starts a Configurable timer. After the timer expires, the VLT ports are enabled one-by-one in a controlled manner. The delay between bringing up each VLT port-channel is proportional to the number of physical members in the port-channel. The default is 90 seconds. To change the duration of the Configurable timer, use the delay-restore command."

RE: 2 FN410T in FX2 in VLT-Mode

Yes, I expected the backup-link to be the Management-IP. And I configured one on each of the IOM. And they are both pingable by each other. Than I used the VLT-Mode wich is kinda autoconfiguration. The PO 127 as VLT-Peer-Link is configured and working. But this mode seems not allowing me to configure the VLT-Domain.

RE: 2 FN410T in FX2 in VLT-Mode

You should be able to use the command # back-up distention, to make the change to the management IP.

The service should not be interrupted when just one switch is down. When you said the connection to the server was lost for a minute, I thought you meant the connection to the switch that was reloaded. But I guess you meant ALL connections to the servers were lost, including the switch that stayed up? If that is the case, then that is not normal operation. Did the logs record anything during this time?

RE: 2 FN410T in FX2 in VLT-Mode

The back-up command will be present under the vlt domain.

# vlt domain 1# back-up destination x.x.x.x

I suggest getting the backup destination set correctly. Perhaps reduce the timer to 30 or 60 seconds. Look through that best practice list for any other tweaks that can be made. Then test again, hopefully the changes will get rid of the loss of connection that you saw.